Pervious Urachus* 



By C. L. Wilhite, D. V. S. Manilla, la. 



During the latter part of the period of ges- 

 tation the urine passes from the fetus through a 

 canal or tube into the allantoid cavity (a space 

 between the outer and inner folds of the placenta, 

 the chorion and amnion, and lined with the mid- 

 dle fold of the allantois) . This canal is called the 

 urachus. When parturition begins this urine con- 

 tained in the allantoid cavity is a part of the fluid 

 that passes when the placental envelopes break. 



Some authorities claim that pervious urachus 

 is caused by a stricture of the urethra, but I have 

 found such to be the cause in only a few of many 

 cases that I have met. I believe it is caused by 

 some freak of nature or a disease which prevents 

 closure of the urachus at the bladder at birth or 

 soon afterwards. 



♦Reprinted from the American Journal of Veterinary Medicine, 

 December, 1911. 



